Off-The-Grid Home Water System

Updated on February 24, 2016

Entrance to an Earthship - off the grid and fully sustainable - located outside of Taos, New Mexico, USA. | Source

We in the Western world have a habit of using water once, then discarding it, taking more to use just once and discarding that too, without thought. We take what fresh water we can and pollute the rest. We use drinking water to wash clothes, flush toilets, and water plants (which actually prefer richer water).

The practice is not functional, for now we are running out of healthy water. As populations grow, the problem grows worse. We have too many dams. We're throwing too much good water into the ocean. Statistics show that earth has only 1% fresh water, but if we keep throwing it away like we are, how much will we have in the end?

Water Supply System - Where Do We Stand?

When humans designed the system for automatically supplying drinking water from dams to homes, it transformed our lives and drained the earth. Now we're designing projects that purify soiled water on a grand scale to return to the aquifer, hoping to refill what we've depleted. These grand projects require millions of dollars to build and in these days of economic turmoil we don't have the money to spare . . . yet water can make the difference between life and death.

Calumet Water Reclamation Plant, designed to treat wastewater from 300 square miles of Chicago and some of its suburbs. Provides primary and secondary treatment, removing 90% of the water's contaminants. | Source

In order to survive and thrive again, we need a water supply that is more sustainable - something smaller, a new system that everyone can easily embrace, one that can be automated to use and reuse water onsite, discarding as little as possible. We need a new, more efficient, home water supply system.

New Water System: Harvesting & Reusing

What if every household in the world could thrive with just the amount of water they received via rainfall and no more? What if water supply and reuse was built into each dwelling to provide enough drinking and bathing water (hot and cold), enough water to wash clothes and grow food, internal plumbing and toilets, and enough left over for pretty, decorative plants and trees around the home, without taking away from anyone else or the aquifer?

Such a supply would be automatically refreshed whenever it rained. The homeowner would have plenty enough to last until the next rain, because of the way the system was set up. The technology could spread all over the world and improve the lives of millions. Impossible, you say? Not anymore.

Earthship Homes - Water Supply

In Taos, New Mexico a group of pioneers gathered around architect Michael Reynolds in the 1970s to design and build wholly sustainable dwellings using local materials. In the process, they devised an entire system of water supply and use/reuse that has been proven self sufficient for the last 20 years. This system allows for fully functional living in areas that get as little as 7" of rainfall per year, without additional supplementation.

In other words, Earthships operate almost completely separate from the grid, dependent only upon themselves and rainfall for their water supply. The technology, now fully developed, is catching on worldwide. Earthships have been built in Canada, Australia, Europe, India, the Caribbean, Latin America, and Africa.

The Earthship system is a complete-cycle system, which can be adapted to the "normal" homes in which most of us live. Although its technology can be used as a model for complete sustainability for all types of buildings, in our own homes we can purchase parts of it to install, using existing plumbing, until we are as self-sufficient as possible.

Earthship Demonstration Project - This is like a real estate model home, showing the window side of the house. | Source

Earthship Roof - Earthships are built into small hills, with the window side facing south and the other sides insulated by earth. | Source

How the Water Harvesting & Recycling System Works

The Earthship's initial water supply comes from the rain. Clean rainwater is used for drinking, cooking, and washing. Discarded water from those activities goes to feed indoor edible plants, which filter the water sinking down through their soils. Water left over from that goes to flush the indoor toilet/s. Flush water goes outside to water outdoor, mostly decorative plants and trees, where it is used up. Nothing is left, nothing goes into the aquifer to contaminate the groundwater. Nor is groundwater used up while waiting for rain.

Rainwater Capture - The bowl you see here is a sieve leading to a silt filter pipe that descends to a buried cistern. All Earthship roofs are curved to direct rainwater toward the sieves and their cisterns.

Rainwater Purification System - These filters assure that rainwater meets local drinking quality standards. Water is purified as it moves from the cistern to a pressurized holding tank.

Solar Water Heater - The pipe leading to the bottom of the solar panel supplies it with cold water. The pipe emerging from the top of it carries heated water down to a hot water tank inside the house.

Greywater Filtration Solarium - All plants in this solarium, mostly edible, are fed by water discarded from sinks, showers, and the washing machine. Excess water goes from here to flush toilets, after filtration through the soil. | Source

Here are the details of this fully contained water supply and use system:

Rainwater harvesting- Earthship roofs are made from nontoxic materials, with gutters that catch and direct rain into cisterns. On the way down, the rain is passed through a silt filter to take out dust and other particles. The cisterns are buried in the ground to keep the water cool, their size depending on how often and how much it normally rains.

To feed house faucets, water from the cisterns is pumped through an extensive purification system into a pressure tank that meets local building codes. There it waits until a faucet opens in the house: Sinks, showers, or the solar heating unit.

Solar water heating - Since much of the water used in a house is for washing, and Earthships are built to be entirely self-sufficient, this system provides for heating water using the power of the sun. Solar water heaters are built into the south side of the house, which receives sun most of the day, and heated water is directed from there to the inside faucets. A small, natural gas or electric backup heater is installed for cloudy days.

Greywater Filtration - All faucets lead to water being used for drinking, food preparation, or washing of some kind, using biodegradable soaps. Water discarded from there is called "greywater" and is sent to indoor biological filtering units in the form of planters growing food and herbs. As water sinks down through those soils, what is not used by the plants is cleaned well enough to be sent through pipes to flush toilets.

Blackwater Filtration - Water flushed from toilets is called "blackwater." In this complete-house system, blackwater is sent to rubber-lined planters outside the house to be used primarily by decorative plants and small trees.

For those homeowners who prefer a more standard treatment, blackwater can be sent to a conventional septic tank that is solar heated to enhance the anaerobic digestion of sewage. From there it goes to leach fields through underground trenches - perforated to let the effluent seep into the soil. Nematode colonies in the soil break down any remaining pathogens before water reaches the water table.

What is discarded? Nothing. Every bit of captured rainwater is used in some way. This negates the need for miles of sewage pipelines and expensive sewage treatment plants to treat what could be taken care of right in a person's home. It also negates the need for fertilizers to grow healthy plants in the yard, since the soil is naturally fertilized with greywater (indoors) and blackwater (outdoors).

Think of the millions of dollars that municipalities and residents could save from this kind of home sewage treatment system alone. Then think of the millions of dollars that could be saved by capturing all water needed in a home from locally available rainwater, instead of having it piped in from elsewhere. It goes without saying that all house appliances in this system would be both water conserving and energy efficient, thereby saving even more money from what is currently spent in the western world.

Water Supply and Health Cost Savings

Local water utilities could be built much smaller to supply manufacturing facilities only. Rivers could be left to flow naturally to replenish the land or, if diverted, used primarily for agriculture. More than half of the existing dams could be broken up to allow water to replenish the aquifer, instead of merely evaporating.

There would be no need for chemicals to be added to purify water collected and shipped for miles cross country. Food transport from country to country would be minimized, since most homes would grow their own, and carbon emissions would decrease dramatically. Tension between communities and countries vying for water and food would decrease to the point that war could be avoided.

Introduction to Earthships

Think of how much money governments could save if:

Water utilities were built smaller, with fewer and shorter pipelines to maintain.

Sewage treatment facilities were not needed - every building would have their own.

Only half the dams were needed, cutting down on maintenance costs.

Chemical treatment of water were decreased or eliminated.

Most food was grown locally year round, with indoor greywater planters protected from the weather acting like greenhouses, minimizing the need for long distance transport.

Home garden maintenance was taught in schools, thereby increasing the health of all families.

Every country was self sufficient with water supply and food, reducing costly conflicts for those resources.

Such an automated water supply system for all homes would make a huge impact in the world. It would benefit not just individuals, but governments and the earth itself, saving money and time, and reducing pollution from sewage and rain runoff.

Economic Changes from Harvesting & Recyling Water at Home

Of course, the world economy would have some adjusting to do. Massive water-related construction projects would decrease, but the need for manufacture of home system components would increase. Utilities would become smaller, but the number of home plumbing and repair jobs would grow. The building and landscaping industries would change their practices, but still thrive. The food transportation industry would decrease, but people transportation would likely go up again. Small and medium size repair shops, plumbers, and electricians would thrive. And fewer people around the world would die of starvation or thirst - a good tradeoff, overall.

Comments 8 comments

Really interesting, I'm in the process of making my home as self sufficient as possible. I am at this moment enjoying the heat of the woodstove I was given this summer. A friend of mine built me a stone wall from leftover materials from a job. I love it. Be looking forward to reading more. Beth

LongTimeMother 3 years ago from Australia

We live off the grid and collect our own rainwater. Grey water is diverted to the roots of fruit trees etc but I don't use it on herbs or veges. Black water goes in the septic tank. In theory the grey water could be used in the loo, but I'm happy to water the garden and keep the plants strong

Large water tanks could easily be incorporated in every house design. They come in all kinds of shapes and sizes these days. :)

watergeek 3 years ago Author

I cannot wait for the day that all buildings are constructed with rain collection and greywater systems built in. It just makes so much sense, and would save so much potable water.

Arco Hess Designs 2 years ago from Kansas City, Kansas

This is something more people need to do. Rainwater has many, many uses, especially in Western countries where people want to keep their lawns green and in desert areas where rain is scarce.

watergeek 2 years ago Author

I agree. And I just found out that Los Angeles is developing a policy that will include massive cisterns under the city to help reduce our need for imported water. That is good news.

Kristen Howe 20 months ago from Northeast Ohio

Great hub, Watergreek. It's so interesting and informative about home rain water being harvesting. Voted up!

Besarien 19 months ago

Earthships are amazing! We have some solar panels with a battery system and a rain barrel that collects water from the roof to water the garden. Still a long way from living off grid, but trying to get a little more self sufficient every year.

watergeek 19 months ago Author

I can't wait to see the explosion in technology (and our economy), when the government "gets it" that community self-suffiency is more efficient than giant dams and water transport systems (for example). Good for you for starting the process, Besarien.